The invention relates to a setting tool comprising a housing, a firing device arranged inside the housing, a piston guide axially displaceable in the housing with a cartridge magazine and an axially displaceable driving piston, and at least one guidance element cooperating with the firing device. Centering means act between the piston guide and the housing, and guidance elements, by means of the centering means, are arranged on at least one of the piston guide and the firing device and are coaxially disposable relative to corresponding receiving openings on at least one of the piston guide and the firing device.
In explosive powder operated setting tools, the piston guide can be disassembled and removed, in the setting direction, from the rest of the setting tool for maintenance and service purposes.
At assembly, the piston guide must have a certain position relative to the firing device so that a trigger element, for example, a contact pin, which projects from the piston guide, in the setting direction, can pass through an opening into the ignition device to cooperate with the ignition device. Similarly, an alternate trigger element, such as an axially displaceable control pin for the power regulation device, projects from the stop surface of the ignition device to cooperate with a corresponding opening in the opposing surface of the piston guide.
The requisite disposition of the piston guide opposite the ignition device or the trigger elements opposite the access openings is done visually and requires that the user be familiar with the tool. Moreover, the user must align the piston guide opposite the ignition device prior to installing the piston guide in the housing.
The object of the invention is to provide a setting tool in which the piston guide can be aligned opposite the ignition device quickly, reliably and properly without requiring the user to visually align both parts.
This object is achieved by the setting tool of the present invention. The setting tool comprises a housing, a firing device arranged inside the housing, a piston guide axially displaceable in the housing with a cartridge magazine and an axially displaceable driving piston, and at least one guidance element cooperating with the firing device, wherein centering means act between the piston guide and the housing. Guidance elements, by means of the centering means, are arranged on at least one of the piston guide and the firing device and extend essentially parallel to the setting direction and are coaxially disposable on at least one of the piston guide and the firing device relative to corresponding receiving openings on at least one of the piston guide and the firing device.
The assembly of the piston guide in the housing of the setting tool and the very quick, simple and reliable alignment of the piston guide relative to the ignition device is possible because of the centering means of the setting tool of the invention.
Preferably, economical and easy-to-manufacture centering means comprise at least one centering lug and at least one guide groove a centering means, wherein the centering lug is disposed on the piston guide or on the housing and the guide groove is disposed on the piston guide or on the housing. The length of the centering lug extending parallel to the setting direction can be fashioned very short or can have the form of a rib with a greater length.
For manufacturing process reasons, the centering lug is preferably part of a centering ring encompassing the piston guide and cooperates, in a non-rotational manner, with the piston guide. The ring is simple to manufacture and easily connected to the piston guide.
The centering ring is displaceable, in the setting direction, against the force of a spring element such that the length of the guide groove can be kept short.
A rotational key of the centering ring is provides a rotationally resistant connection of the centering ring along the piston guide. The rotational drive projects into the inside space of the centering ring. The centering ring projects into a rotational key way and is arranged on the piston guide, extending parallel to the setting direction. The key way is, for example, a projection of the centering ring that extends into the inside space of the centering ring.
A space between an opening of the guide groove, on the setting side, and a stop surface of the firing device, facing in the setting direction, is greater than a maximum space between the centering lug and the free end of an initial trigger or guidance element facing away from the setting direction. Additionally, the space can be greater than the sum of the space formed by the space between the centering lung and the opposing surface of the piston guide and the space between the stop surface of the firing device and the setting-side end of a second control or trigger element. This space is provided to make it possible for the piston guide, when inserted into the housing, to be rotated relative to the firing device for the peripheral mutual alignment, without a control or trigger element preventing the rotation. Preferably, this rotation occurs with the setting tool in an unassembled state.
Preferably, at least one part of the guide groove is a centering sleeve open on the setting-side that is fixed, in a receiving space of the housing, to prevent damage to the receiving bore of the housing.
Preferably, the trigger or guidance element projecting from the piston guide is a contact pin that cooperates with the firing device. The trigger element projecting from the firing device is formed by an axially displaceable control pin of a power regulating device.
Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings.